1. Field of the Invention
The present invention is related to the structure of a forceful grinding medium, and especially to the structure of a grinding medium formed with a plurality of raised and circle shaped blades for obtaining dense and smooth grinding processing areas in a mode of three dimensional vibration grinding, so that grinding efficiency of a lot of such forceful grinding media on a workpiece can be improved. The forceful grinding media which are producible,stainless steel sheets or spring steel sheets can be chosen and heat treated after punch molding to get desired suitable hardness and toughness for use, or they can be formed by sintering in the mode of powder metallurgy to obtain the required hardness and toughness for use.
2. Description of the Prior Art
The technique of three dimensional vibration grinding for polishing workpieces has been very popular and widely used, whereby, grinding granulars are chosen with respect to size, hardness and shape thereof according to the material of a workpiece to be ground and the outlines of the workpiece to be ground and polished. This cooperates with the formulation of the grinding liquid required to have the workpiece processed in a vibration tank of a vibration grinder.
It has been known that the grinding granulars are mixed in the grinding liquid. These grinding media (or grinding granulars) are made of plastic, stones or ceramic material of various hardness, mass and shapes. The selection of the hardness of these grinding media is significantly concerned with the hardness of the workpiece to be ground in the three dimensional collision grinding process with high frequency vibration, in order that the casting of the workpiece can be well polished with the grinding media and produce a workpiece with the desired brightness and smoothness. Furthermore, the unit volume and quantity of the grinding media must be in a certain mutually balanced proportion to the workpiece to be ground, such that the disturbance collision efficiency between the grinding media and the workpiece can be accurately controlled. In addition, the size and shape of the grinding media must be properly chosen in accordance with the shapes of the minimum grooves, ribs or holes on the workpiece to be ground in order to facilitate turning over and collision thereof on the grooves, ribs or holes. Elements such as the cutting angle that may be induced in the grinding tank, the vibration frequency, orientation as well as the disturbance feature of the grinding liquid etc. are also the important factors deciding the effeciency and quality of the vibrational grinding.
However, conventional techniques of vibrational grinding in the art can only be effective on the softer alloy workpieces to be ground. The reason that it is inferior in accuracy and efficiency of grinding on the harder alloy workpieces such as stainless steel, titanium alloy, chromium and molybdenum alloy, etc. is that, when in grinding by the conventional techniques, only plastic, stones or ceramic material etc. are used as the grinding media.
Moreover, conventional grinding media physically are less efficient in grinding and cutting. Area distribution of the processing cutters for smooth grinding and cutting on the surfaces thereof is very limited. The limited number of the cutters is not good for the efficiency of three dimensional collision grinding and cutting.